<template>

  <div class="app-container">

    <h2 style="text-align: center;">发布新课程</h2>

    <el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">
      <el-step title="填写课程基本信息"/>
      <el-step title="创建课程大纲"/>
      <el-step title="提交审核"/>
    </el-steps>

    <el-form label-width="120px">

        <el-form-item label="课程标题">
            <el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写"/>
        </el-form-item>

        <!-- 所属分类 TODO -->



        <el-form-item label="课程分类">
            <!-- <el-select v-model="courseInfo.subjectId" placeholder="请选择">
                <el-option-group
                    v-for="group in subjectList"
                    :key="group.id"
                    :label="group.title">
                    <el-option
                        v-for="item in group.children"
                        :key="item.id"
                        :label="item.title"
                        :value="item.id">
                    </el-option>
                </el-option-group>
            </el-select> -->

            <el-select v-model="courseInfo.subjectParentId" @change="getTwoSubjectList" placeholder="请选择一级分类">
                <el-option
                    v-for="item in subjectList"
                    :key="item.id"
                    :label="item.title"
                    :value="item.id">
                </el-option>            
            </el-select>

            <el-select v-model="courseInfo.subjectId" placeholder="请选择二级分类">
                <el-option
                    v-for="item in twoSubjectList"
                    :key="item.id"
                    :label="item.title"
                    :value="item.id">
                </el-option>            
            </el-select>

        </el-form-item>




        <!-- 课程讲师 TODO -->
        <el-form-item label="课程讲师">
            <el-select v-model="courseInfo.teacherId" placeholder="请选择">
                <el-option
                    v-for="item in teacherList"
                    :key="item.id"
                    :label="item.name"
                    :value="item.id">
                </el-option>            
            </el-select>
        </el-form-item>

        <el-form-item label="总课时">
            <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder="请填写课程的总课时数"/>
        </el-form-item>

        <!-- 课程简介 TODO -->
        <!-- 课程简介-->
        <el-form-item label="课程简介">
            <tinymce :height="300" v-model="courseInfo.description"/>
        </el-form-item>



        <!-- 课程封面 TODO -->

        <!-- 课程封面-->
        <el-form-item label="课程封面">

            <el-upload
                :show-file-list="false"
                :on-success="handleCoverSuccess"
                :before-upload="beforeCoverUpload"
                :action="BASE_API+'/oss/file/courseCoverUpload'"
                class="avatar-uploader">
                <img :src="courseInfo.cover">
            </el-upload>

        </el-form-item>

        <el-form-item label="课程价格">
            <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder="免费课程请设置为0元"/> 元
        </el-form-item>

        <el-form-item>
            <el-button :disabled="saveBtnDisabled" type="primary" @click="saveOrUpdate">保存并下一步</el-button>
        </el-form-item>
    </el-form>
  </div>
</template>

<style scoped>
.tinymce-container {
  line-height: 29px;
}
</style>



<script>

import * as course from '@/api/edu/course'   

import * as subject from '@/api/edu/subject'  

import * as teacher from '@/api/edu/teacher'  

import Tinymce from '@/components/Tinymce'

export default {
    components: { Tinymce },
    data(){
        return{
            saveBtnDisabled:false,
            courseInfo:{  
                title: '',
                subjectId: '',
                teacherId: '',
                subjectParentId:'',
                lessonNum: 0,
                description: '',
                cover: '',
                price: 0
            },
            teacherList:{

            },
            subjectList:{

            },
            twoSubjectList:{

            },
            BASE_API:process.env.BASE_API
        }
    },
    created(){
        this.init();
    },
    watch: {
      $route(to, from) {
        this.init()
      }
    },
    methods:{
        saveOrUpdate(){
            if (this.$route.params && this.$route.params.id) {
                course.updateCourseInfo(this.$route.params.id,this.courseInfo)
                    .then(response =>{
                        this.$message({
                            type:'success',
                            message:'修改课程成功'
                        })
                        this.$router.push({path:'/course/chapter/' + response.data.courseId})
                    })

            }else{
                course.addCourseInfo(this.courseInfo)
                    .then(response =>{
                        this.$message({
                            type:'success',
                            message:'添加课程成功'
                        })
                        var courseId = response.data.courseId;
                        this.$router.push({path:'/course/chapter/' + courseId})
                    })
            }
        },
        init(){  
            teacher.getTeacherAllList()
                .then(response =>{
                    this.teacherList = response.data.items 
                })
            subject.getSubjectList()
                .then(response =>{
                    this.subjectList = response.data.list
                    if (this.$route.params && this.$route.params.id) {
                        const id = this.$route.params.id
                        this.getCourse(id)
                    }  
                })
            this.courseInfo={  
                title: '',
                subjectId: '',
                teacherId: '',
                subjectParentId:'',
                lessonNum: 0,
                description: '',
                cover: '/static/timg.jpg',
                price: 0
            }
        },
        getTwoSubjectList(){
            this.courseInfo.subjectId = '';
            for(var i = 0 ; i < this.subjectList.length ; i++){
                if(this.subjectList[i].id == this.courseInfo.subjectParentId){
                    this.twoSubjectList = this.subjectList[i].children;
                    break;
                }
            }
        },
        getCourse(id){
            course.getCourseInfo(id)
                .then(response =>{
                    this.courseInfo = response.data.courseInfo;
                    var tempId = response.data.courseInfo.subjectId;
                    this.getTwoSubjectList()
                    
                    this.courseInfo.subjectId = tempId;
                })
        },
        handleCoverSuccess(res,file){
            console.log(res)// 上传响应
            console.log(URL.createObjectURL(file.raw))// base64编码
            this.courseInfo.cover = res.data.url
        },
        beforeCoverUpload(file){
            const isJPG = file.type === 'image/jpeg'
            const isLt2M = file.size / 1024 / 1024 < 2

            if (!isJPG) {
                this.$message.error('上传头像图片只能是 JPG 格式!')
            }
            if (!isLt2M) {
                this.$message.error('上传头像图片大小不能超过 2MB!')
            }
            return isJPG && isLt2M
        }
            



    }



}
</script>

